Synthetic adjuvants will be utilized to selectively potentiate T cell subset functions directed against syngeneic tumor cells. These functions will be analyzed using distinct assays such as the generation of cytolytic T lymphocytes against syngeneic tumor cell surface antigens, amplification of the cytotoxic T cell (CTL) response by the helper T cell subset, and the generation of cytolytic antibody directed against syngeneic tumors. In addition, the potential of synthetic adjuvants to generate suppressor T cells which may regulate the activity of cytolytic T cells against tumors in vitro and in vivo will be assessed. The two models chosen will focus on the period of tumor remission obtained between the time that the primary tumor is identified and the expected onset metastatic disease which occurs as the animals age. Immunotherapeutic protocols using highly activated subpopulations of T lymphocytes together with adjuvants will be tested. In addition, if adjuvants are found to induce suppressor cells in vivo, regimes will be undertaken to circumvent the induction of suppression in vivo. These protocols include thymectomizing the animal, pretreating the animal with cytoxan to reduce the possibility of the induction of suppression, and in vivo administration of anti Ig anti-serum. These experiments should provide a rational basis for the utilization of adjuvants and specifically activated T cells in tumor-bearing mice.